It depends a lot on what kind of person u are. if u need to have good sound, no matter what the cost, u should use bronze. bronze sounds the best, but the sacrifice u make is having to change strings a lot, because bronze wears and dies the fastest (dies after a few hours of playing). nickel on the other hand is very durable, but doesn't sound as good as bronze. its better to use nickel if your lazy and hate replacing strings or if you just don't want to spend more money to buy more strings and you don't care much about your sound. basically, bronze is best for live playing. nickel is best for practicing and playing for fun